I was getting it constantly too but it turns out this is warning you that your back cover is not sealed all the way. You need to put the back cover properly by starting by pressing from the center out (near the camera is the first snap that needs to be pressed in) and continue to press down outwards like the arrows show on the plastic cover that was on the back when you received the phone.

I get this on every reboot and I have pressed the back cover onto the phone as good as possible.
Is my phone broken somehow or is that normal behaviour?

It appears for a few seconds after unlocking until touchwiz seems to redraw.
I don't get it constantly but only on reboot. I'd like my phone to be watersealed.

It's normal, no worries. You should also get a warning about the usb port cover whenever you unplug a charger. These are just normal behaviors for the phone, reminding people to double check and make sure everything is sealed up properly.

It's normal, no worries. You should also get a warning about the usb port cover whenever you unplug a charger. These are just normal behaviors for the phone, reminding people to double check and make sure everything is sealed up properly.

+1.
Spot on - This is a generic message and does not mean your back is not secure, I see no sensor that the device could use to determine that the back or usb cover is not fully sealed. No way there is a switch at every tab for the back.
As for the USB cover I also get that after unplugging the USB and every reboot. Regardless of actual cover position.

After numerous times of seeing the warnings, I'm pretty sure I could keep it sealed without being notifiedů
A way to remove these annoying warnings would make using this phone a whole lot more pleasant..

After numerous times of seeing the warnings, I'm pretty sure I could keep it sealed without being notifiedů
A way to remove these annoying warnings would make using this phone a whole lot more pleasant..

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